Chapter 39. Migrating from Titan

This page describes some of the Configuration options that JanusGraph provides to allow migration of data from a data store which had previously been created by Titan. Please note after migrating to version 0.3.0, or later, of JanusGraph you will not be able to connect to a graph using a Titan client.

39.1. Configuration

When connecting to an existing Titan data store the graph.titan-version property should already be set in the global configuration to Titan version 1.0.0. The ID store name in JanusGraph is configurable via the ids.store-name property whereas in Titan it was a constant. If the graph.titan-version has been set in the existing global configuration, then you do not need to explicitly set the ID store as it will default to titan_ids.

39.2. Cassandra

The default keyspace used by Titan was titan and in order to reuse that existing keyspace the storage.cassandra.keyspace property needs to be set accordingly.

storage.cassandra.keyspace=titan

These configuration options allow JanusGraph to read data from a Cassandra database which had previously been created by Titan. However, once JanusGraph writes back to that database it will register additional serializers which mean that it will no longer be compatible with Titan. Users are therefore encouraged to backup the data in Casssandra before attempting to use it with the JanusGraph release.

39.3. HBase

The name of the table used by Titan was titan and in order to reuse that existing table the storage.hbase.table property needs to be set accordingly.

storage.hbase.table=titan

These configuration options allow JanusGraph to read data from an HBase database which had previously been created by Titan. However, once JanusGraph writes back to that database it will register additional serializers which mean that it will no longer be compatible with Titan. Users are therefore encouraged to backup the data in HBase before attempting to use it with the JanusGraph release.

39.4. BerkeleyDB

The BerkeleyDB version has been updated, and it contains changes to the file format stored on disk. This file format change is forward compatible with previous versions of BerkeleyDB, so existing graph data stored with Titan can be read in. However, once the data has been read in with the newer version of BerkeleyDB, those files can no longer be read by the older version. Users are encouraged to backup the BerkeleyDB storage directory before attempting to use it with the JanusGraph release.